Internal combustion engine



J. J. MCCARTHY INTERNAL COMBUSTiON ENGINE Filed May 13, 1940 2 Sheets-Sheet, 1

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J. J. M CARTHY INTERNAL COMBUSTION ENGINE Filed May 15, 1940 2 Sheets-Sheet 2 a 1 i a M 2+ 1 r m 4 e m. 2 Q M w a a 0 2 0 4 1 Q 2 5 K Z 4 OQMQM/W J M W L .4 4 M, u

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Patented Sept. 2, 1941 UNITED STATE s' PATENT I OFFICE INTERNAL COLIBUSTION ENGINE John J. McCarthy, Maiden. Mass, mlgnor to Mary E. McCarthy, Maiden, Mass.

Application May 1a, 1940, Serial No. 334,738

22 Claims.

This invention relates to internal combustion engines, and more particularly to engines of the compression ignition type.

It is the primary aim and object of the present invention to provide a multi-cylinder engine in which the intake air effectively cools the cylinders and more particularly the pistons therein.

It is another object of the present invention to provide for the cooling of the hot lubricant o! a circulatory lubricating system by the intake air.-

It is another object of the present invention to provide an engine for aviation purposes in which a plurality of separate iron cylinders are independently mounted on the crank case of a lightweight material so that the diflerent expansion of nates a crank case in which a crank shaft II is journalled and held against axial movement in main'bearings i2, provided by the crankcase i and bearing caps ll. A'suitable cover It is the cylinders and crank case does-notinduce any.

stresses in the same and interfere. with the smooth performance oi. the movable engine parts.

I It is also among the objects of the present inv'ention to provide a manually operable brake on the propeller-shaft of an aviation engine in order to enable the pilot to stop said shaft and'therewith the engine itself when the engineis or has I to be shut off in mid-air and the air "dragon the, propeller tends to revolve the latter.

. Before explaining in detail the present invenmounted on the open top of the crank case. In-,

tegralxwith the crankcase and projecting therei I into are two rows of cylinder sleeves l which are arrangedlin a'V and merge at their adjacent top ends as at I] (Fig. 3). Preferably independently mounted asby bolts (not shown). on thecrank case l0 and-incoaxial alinement with the cylin- I der-sleeveslt thereof, are separate-cylinders l'l whose outerends I! are open and in communica- I tion with an air chamber '19. This air chamber is is defined by the bottom.wall of the crank case ID, the adjacent halves of the two'rows of tion, it is to be understood that the invention is not limited in its application tothe details of construction and arrangement of parts illustrated in the accompanying drawings, sincethe.

invention is capable of other embodiments and of being practiced or carried out in various ways. Also it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation, and it. is not intended to limit the invention claimed irerein beyond the requirements of the prior art.

In the drawings:

cylinders l'| including the ribs 2i (Figs. 1 and 3) a cover- 22 suitably mounted on the open cylinder ends "in the manner shown in 3, and two end walls 22 and 24. of the crank case (Figs. 1 and- ,2). The "engaging ends of each cylinder sleeve Ii and cylinder ii are counterbored to Y provide an annulargroove (Fig. 3) into which Fig. 1 illustrates, partly in section and partly.

in side elevation, an internal combustion engine which embodies the present invention, the sec- 7 ticn being taken substantially on the line l-l' of Fig. 2. i

Fig. 2 is a section through the engine taken substantially along the line 2-2 of Fig. 3, certain parts of the engine being omitted for the sake of clearer illustration of the crank case structure and the cyclinder arrangement.

1 Fig. 3 is a transverse section through the engine taken substantially on the line 3-2 of Figs.

1 and 2..

Fig. dis a sectionthrough a perspectively illustrated detail of thefengine.

Fig. 5 is a section taken substantially on the line 5-5 of Fig. 3.

a centering ring 26 is fitted for accurate alinement'ofsaid cylinder withsaid cylinder sleeve. Provided in the wall of each cylinder sleeve ills a plurality of intake ports 21 which communicate with an intake chamber 28. This intake chamber 28 is formed by opposite portions or the side walls 22 of the crank case, the bottom wall 20 of the crank case (Figs. 2 and3), a partition 30 in the crank case through which the cylinder sleeves [I extend in the manner shown in Figs. 1 and 3, and the previously mentioned end walls 23 arid 24.0! the crank case (Fig. 2). Each rins 28 is also provided with'a plurality ofintake ports 31. (Figs. 3 and 4) which register with the intake ports 21 of the respective cylinder sleeve i5 and are in communication with an internal annular groove 32 in saidring. Furthermore; each ring 26 may be'rotatablymounted inits annular groove 25 and rotatedby-any suitable means (not shown) in orde'r'to' regulate the effective area of the intake ports 21, 3|.

Slidable in each cylinder ll 7 and cylinder sleeve II alined therewith is a sleeve piston I3 whose head II is preferably cup-shaped and providedwith a plurality of cooling ribs II (Fig. 3). Each sleeve piston 33- is connected with the crank shaft- II by means of two connecting rods II and two wrist'pins I1. More-particularly, the

' lower ends of eachpair of connectingrods II are advantage that any bending stressesinduced in forked as at II (Fig. 5) and straddle diametrically opposite, machined portions of the inwardly flanged, open endoi." a sleeve piston. These flange portions are within'the' confines of the outside diameter of the sleeve piston (Fig. 5)

'so that the center of effort of each wrist pin I1 is clearly within said confines. This secures the a sleeve piston 33 by the connecting rods II thereof are eifectively counteracted by the wall of the respective cylinder i I and cylinder sleeve ass-ease v communicates with the atmosphere through a plurality of conduits or scoops II which extend II aiined therewith. Each sleeve piston II is 1 furthermore provided with a multiplicity of relatively small intake openings II and a plurality of exhaust ports II which are adapted to register with the previously mentioned annular groove 32 (Fig. 3) and a circular exhaust chamber If in a cylinder, respectively.- The circular exhaust chamber II of each cylinder in a-row communicates through a passage II with an exhaust manifold II. Slidable in each sleeve piston II is an opposed piston'II which is connected with the crank shaft l I by a connecting rod II. The connecting rods II and II of the pistons in one cylinderrow aremaster rods to which the connecting rods of the pistons in the other cylinder row are connected in a conventional manner.

Each cylinder il in a row is furthermore provided with a water jacket 41, having two ports II and II which communicate with water manifolds II and Ii, respectively (Fig. 3). In one instance, the cooling water for the various cylinthrough the cover 22. More particularly, a scoop II is secured by a spider II (Fig. 3) to the outer open end of each cylinder "and extends into close proximity to the bottom of the cupshaped head of the sleeve piston therein when the' latter is in its outermost position (Fig. 3) so i that the incoming air flows first past the cooling ribs II in said piston head and absorbs some of the heat thereof before entering" the air chamber Mounted on the end wall 23 of the crank case is a twin supercharger II (Figs. 1 and 2) having a common inlet II which communicates with the air chamber II through an opening I'I in said end wall 23 (Figs. 1 and 3). Two rotary impellers II and II of the supercharger draw air from the chamber II through the common inlet a II into es II and II, respectively, and force said air into the intake chamber 2| through discharge chambers I2 and I3, respectively, of the supercharger and admission ports II and II, respectively, in the end wall 23 of-the crank case (Fig., 2). The rotary impellers II and II of the supercharger may be driven in any. suitable manner from the crank shaft II. The present invention being shown embodied in an aviation engine having a driven propeller shaft II, the rotary impellers II and II are preferably driven from the propeller shaft II in the following manner. The impellers are mounted on a suitably iournalled sleeve II (Fig. 1) whose one end is provided with a small gear I! which meshes with a larger gear II on a suitably journalled stub shaft II that carries another gear II which meshes witha larger gear. II, mounted on a suitably iournalled shaft II which passes data I! may be forced by any suitablepump-II through conduits II and II into the manifolds Ila and III), respectively, from there the water passes into andthrough. the cylinder Jackets 41 to the manifolds Ila and Ilb and then through conduits II to any conventional radiator II where the hot water is cooled before being drawn into the pump I2 through a conduit II and recirculated. The cooling water may also be cirin manner atlcally illus-.

trated in Fig. 6, where the water is forced by a pump I!" through conduits II to the water manifolds Ila and lit, and from thereinto and through the cylinder jackets. I1 and then throughflthe manifolds Ila and III) and conduits II" and II'" to a radiator II' in which the water is effectively cooled before being returned to the pump I! through a conduit II'.

Mounted in the wall of each cylinder II is at least one fuel iniector II which communicates through a conduit Ii with any conventional fuel plunger pump I! which is mounted on the crank case II. The plunger II of each fuel pump I! along a cylinder row is operated-by a cam lobe II through the sleeve Ii and is splined at II to the propeller shaft II. In this manner, the rotary impellers II and VII of the supercharger are driven at increased speed from the propeller shaft II. As best shown in Fig. 2, the air admission ports'II and II to the intake chamber II' are in line with the two rowsof cylinder sleeves II, and the cylinder sleeves II of each row are provided with bailies III which preferably decrease in height on consecutive cylinder sleeves.

A These baiiles III are adapted to direct the admitted supercharged air substantially uniformly around the peripheries of the'sleeve pistons so that all the intake ports 21 therein receive approximately the same amount of air. The cyl- I inder sleeves most remote from the air admission ports and II to the intake chamber II require nobafllesastheairisrepelledbytheadiacent end wall II of the crank case and thus forced around said cylinder sleeves.

Mounted on the end wall 23 of the crank case II is a hood "In which houses the supercharger II and a drive between the crank shaft II and the propeller shaft II, the latter being suitably journalled at III and "tin the 2160a "la. The drive between the crank shaft II and the propeller shaft II comprises a Iear III whose hub III is iournalled in suitable bearings III and splined at III to the adjacent end of the crank shaft I I, and a larger gear III which is mounted on the propeller shaft II.

The present engine is lubricated by a circulatory lubricating system which comprises a lubricant reservoir III (Figs. 1 and 3) and means for c rculating the lubricant from the reservoir to the moving engine parts to be lubricated and back to the reservoir. For the sake of brevity and I .case between the two cylinder rows.

because it forms no part of the present invegti the lubricant circulating means is not sho the drawings. It is instead deemed to" explain that lubricant from the reservoir III! is forced in a conventional manner to the crank; shaft 'II which is suitably drilled to conduct the lubricant to the connecting rods 36, 46 and the main bearings I2 from where the lubricant escapes to the cheeks li of the crank shaft. The lubricant is then thrown off the cheeks Ila of the crank shaft and into an auxiliary basin III which is formed in the crank case and whose bottom is the previously described partition wall the lubricant will also splash against the walls ing pistons 33, 45. The ends of the auxiliary basin III communicate with the ends of the lubricant reservoir IIO through cored-out passages II2 in the crank case III (Figs. 1 and 2). The lubricant in the auxiliary basin III is thus immediately returned to the reservoir I III through either one ofthe passages Illregardless of the inclination of the engine when the same is, 1or instance, used in an airplane. As best shown in Figs. 1 and 3,, thelubricant reservoir H9 is {aasaase and the interior of the cylinder sleeves I5. These A 30 through which the cylinder sleeves I5 extend in the manner shown in Figs. 1 and 8. Some of of the cylindefisleeves li and lubricate the slidducts I2I are. normally covered by the sleeve pistons 33 and are uncovered when the intake able for aviation purposes, its total weight has to be assmail as possible. To this end, at least the crank case It is made of a light-weight mterial such as aluminum, while the cylinders H are cast of 'iron. As such a light-weightmaterial as aluminum has a larger coeiiicient of expansion located in the air chamber is and perferably suspended from thebottom wall-20 of the crank In operation, atmospheric air is drawn by the supercharger 15 into the air chamber I9 through the scoops 10. The admitted air flows first into. 7 the outer cylinder ends- I8 andeifectively cools the sleeve piston heads whichbecome very hot as they arein close proximityio the exhaust ports QI-inthe sleeve pistons. The air then flows through the chamber It in heat-exchange relation with the water manifolds 50 and the lubricant reservoir ,I is, with'the result that the cooling water as well as the lubricant'become cooled. The water manifolds 50 as well asthe lubricant reservoir lib may be provided with 'ribsIIS fora more emcient heat exchange It. appears also from Figs. 1 and 3 that substantial-. ly one-half. of the circumference of the water jacket of each cylinder is in heat-exchange rela-,

' tion with the intake air in the chamber I9, whereby the cylinders are further-cooled. 1 From the chamber I9,.'the air is drawn into the supercharger 15, and the supercharged air is expelled into the intake chamber 28 to be admitted at the proper times through the intake ports 2!, 8i and -40 into the cylinder chambers I30 which are formed by each pair of opposed pistons 83, 45.

combustion chambers 66 (Fig. 1) takes place. To provide for straight-through scavenging of the cylinder chambers I20 by the intake air and also I I for retention of suflicient combustion air in said cylinder chambers, .the exhaust-controlling sleeve than cast iron, the cylinders ii are cast separately and are independently mounted-on the crankcase in the 'previouslyexplained manner. In this way, the expansion of the light-weight crankcase I does not induce'any stresses in the cylinders II since the same may individually expand with said crank case. As a consequence, the smoothly performing driving connection between the pistons 33, 45 and the crank shaftII is never disturbed by the difierent ex'pansion of the crank case In and. cylinders I1 and the latter are always f retained in perfect alinement' with their respective 1 cylinder sleeves I5 by the centering rings 26.

-As previously mentioned, the cooling water for the various cylinders may be circulated in the manner illustrated in Fig. 3 or in the manner 11- lustrated in Fig." 6, depending upon the amount of heat permissible in the intake air 'for an emcient combustion.

.Whereas' theengine so far described has a sleeve piston in each cylinder, Fig. '7 shows a modification in which only one piston (not shown) re- At the proper moments injection of fuel into the pistons 33 have preferably a lead over the pistons 45 so that the exhaust 'ports 4I of said sleeve pistons move out of registry with the exhaust passages 42 before the intake ports 21, ii are covered jointly by the pistons a, 45. The annular grooves 32in the centering rings 26 (Figs. 3 and 4) serve as surge ea or chambers 1 through which the intake air is substantially ducts I2I which provide communication between-'- thesupercharged air in theintake chamber a ciprocates in a sleeve I3I in the cylinder I30. The

sleeve BI is 'reciprocated in the same manner as the sleeve pistons 33 in the engine shown in Fig, 3 in order to provide communication between the exhaust ports I32 in said sleeve and the circular exhaust passages I33 in said cylinder. The cylinder head I34 is cup-shaped and provided with cooling ribs I35 and the sleeve I3I is guided between said'cylinder head I34 and the cylinder I30. An air admissionscoop I3Bextends considerably intothe cup-shaped cylinder head I34 so as to conduct the admitted air first against said cylinder head before it flows into the air chamber I31. Thus, each piston head I34, which constitutes one of the hottest spots of the'engine due to its close proximity to the exhaust ports I32, is effectively cooled by theadmitted air.

Mounted on'thepropeller shaft 90 within the hood IBM is a conventional hydraulic brake I40 which enables the pilot of the aircraft to completely stopthe engine after the same is or has to be shut off, in mid-air due to engine trouble orfor. some other reason, and to prevent the air drag on the propeller to turn the engine over.

prevent further damage to a damaged engine after the same is shut oil and while the aircraft are pivotallymounwd is still in the, air. The brake I40 comprises the usual drum i4I which is mounted on the propeller shaft and is adapted to cooperate preferably with two opposite brake shoes I42 which on abracket I43 in the hood IIiIia. The brake shoes I42 are normally 4 urged toward each other and out of braking engagement with the drum Ill by means of a spring. I, while opposite pistonsin the usual master 1 I cylinder I45, which is mounted on a bracket I A and outer ends, respectively; a sleeve memberslidable ineach cylinder member and constituting together with the latter a unit and havingintake andexhaust ports-adapted to register with the corresponding cylinder ports; a piston slidable in each sleeve member andadapted to cover and uncover the intake ports, therein; ahead on the outer end of a member .of each unit forming together'with' the sleeve member of said unit and the piston therein a cylinder chamber-fa first chamber separated from all cylinder chambers by said heads; a second chamber surrounding,

the intake ports 'of all cylinder members: and

'. means providing communication between said first and second chamber, said first-chamber having air admission ports so arranged that said heads are in heat-exchange relation with the admitted air,

2. The combination in an internal combustion engine as set forthin claim 1, in which said means is a supercharger whose intake and exhaust sides communicate with said first and second chamber, respectively. p

3. The combination in an internal combustion engine as set forth in claim 1, further comprising arranged that said outer cylinder ends are in the path of fiow of the admitted air.

8."The combination in an internal I engine as set forth in claim 'L'in which said air admission ports extend into said outer cylinder ends so that the admitted air fiows first into the'latter and then'intc said first chamber.

9 In an internal combustion engine, the combination of two rowsof cylinders arranged in a intake and exhaust ports adapted to register with the corresponding cylinder ports; a-iirst chamber surrounding the intake ports of alleirlinders; a

' said outer cylinder ends opening into said second chamber; and a supercharger at one end of the a circulating lubricating 'systemincluding a 111- bricant reservoir located in said first chamber'inthe path of flow ofthe admitted air.

4. The combination in an internal combustion engine as set forth in claim 1, further comprising acooling jacket on. the cylinder members, a pump, and means providing a circuitous path for a cooling liquid between the pump and jacket and including a conduit leading from the jacket to the. pump and extending in said first chamber in heat-exchange relation with the admitted air.

- 5. The combination in an internal combustion engine as set forth in claim 1, further comprising-a jacket on each cylinder member, a. pump,

and means providing a circuitous path for a that said outer cylinder ends are in heat-exchange relation with the admitted air. a

10. The combination in an internal combustion engine as set forth in claim 9, further comprising a separate jacket oneach-cylinder, a pump, and means providing a circuitous path for a cooling liquid between the pump and each jacket and including a manifold connectingeach Jacket with the pump and extending in said second chamber in heat-exchange relation with the admitted air.

11. The combination in an internal cgmbustion engine asset forth in claim 9, further comprising a Jacket'on each cylinder, a radiator, a pump having its intake side connected with-the discharge side of said radiator, a first manifold connectlng each jacket with the intake side of said cooling liquid between the pump and each Jacket and including a manifold connecting each Jacket with the pump and extending in said first chamber'in heat-exchange relation with the admitted air. I 6."Ihe combination in an internal combustion engine as set forth in claim 1, in which said means is a supercharger whose intake and ex-, haust sides communicate with said first and second chamber, respectively, and baiiies are provided in said second. chamber'for directing the supercharged air to the intake ports of all cylinde'r members.

7. In an internal combustion engine, the combination of a plurality of cylindersopen at both ends and having intake and exhaust ports near its inner and outer end, respectively; opposed pistons in each cylinder, one being a sleeve piston cylinders open; a second chamber surroundingradiator and extending in said second chamber in heat-exchange relation with the admitted air,

and two manifolds extending alongside the cyl-.

inder rows outside of the Vand connecting the jackets of said cylinder rows, respectively, with the discharge side of the pump.

12. The combination in an internal'combustion engine as set forth in claim 9, further comprising a 'jacket on each cylinder, a radiator, a p having its intake. side connected with the discharge side of said radiator, a first manifold connecting each jacket with the discharge side of the pump and extending in said second chamber in heat exchange relation with the admitted air, and two manifolds extending alongside the'cylinder rows outside of the V and connecting the jackets of said cylinder rows, respectively, with the intake side of the radiator.

13. In an internal combustion engine, the combination of a cylinder having an annular recess in its cylindrical wall and a first intake port opening into said recess; a ring rotatable in said recess and being flush with the cylinder wall and having an internal peripheral groove'and another intake port providing communication between said first port and groove; and opposed pistons in theeylindenone being a sleeve piston having intake openings which are distributed aroimd itssleeve and adapted to communicate with said groove, and the eifective area of said ports 14. In an internal combustion engine, the com-- bination of a. crank-case having a. first cylinder member integral therewith, a second cylinder member secured to said first member in axial alignment therewith and forming together with the latterone cylinder, the adjacent ends of said members being countersunk to form an annular groove in the cylinder wall'and at least one of said members having a first intake port opening into said groove; and a ring rotatably mounted in said groove and having another intake port in communication with said first port, said ring accurately aligning said members and, on being turned, varying the effective area or said ports.-

15. The combination in .an internalcombustion engine as set forth in claim 14, further coinprisrality .of minute holes inits wall providing coinmunicatio'n between a source of compressed air supply and the intake ports in the sleeve piston when the pistons are substantially in their inner most position whereupon compressed air escaping through said holes blows lubricant from the iritake ports in said sleeve piston.

ing opposed pistons in the cylinderof which one is r a sleeve piston having intake'openings distributed material and being separately secured to said first members in axial alignmentwith the same, each pair of aligned members forming one cylinder,

' and the adjacent ends of said menibers being countersunk to form an annular groove in the cylinder wall and at least one member of each pair having a first intake port in communication with the countersink thereof; and a ring mounted inveach of said cylinder grooves and having cleared by the other piston when both pistons are 20. In an internal combustion engine, the combination of a cylinder having intake and exhaust ports in its wall; a chamber surrounding'the intake ports; a supercharger delivering compressed air to said chamber; opposed pistons in the cylinder of which one is a sleeve piston having intake and exhaust ports adapted to register with the corresponding cylinderports, the intake ports in said sleeve piston being a multitude'of small intake openings which are nearer the open end of r the sleeve than the exhaust ports therein and substantially in their innermost position: and

means for lubricating the sliding surfaces of both pistons, said cylinder having a multitude of mi- I nute holes in its wall providing .communication between said chamberand said-intake openings I when the pistons are substantially in their innermost position whereupon compressed air escaping through said holes blows lubricant from said intake openings.

- outer ends, respectively: a sleeve member slidable in each cylinder member and constituting to-- gether with the latter a unit and having intake an intake port in communication with said first port, said rings maintaining said members accu-- rately aligned at all temperatures.

17. The combination in an internal combustion engine as set forth in claim 16, in which said rings are rotatably mounted in said cylinder grooves to 21. In an internal combustion engine, the combination of a plurality of cylinder members having intake and exhaust ports near their inner and and exhaust ports adapted to, register with the corresponding cylinder ports; aipistonslidabl'e in each sleeve member and adapted to cover and uncover the intake ports thereim-a head on the outer end .of a member or each unitforming together with the sleeve member 01 said unit and the piston therein a cylinder chamber: and another chamber separated from all cylinder champermit variation of the effective area of said intake ports;

18. The combination in an internal combustion bers by said heads and communicating with the.

Y intake ports of all cylinder members and havin engine as set forth in claim 16, further comprisin opposed pistons in each cylinderor which one is a sleeve piston having a plurality of intake openings distributed around its sleeve, and each of said rings having in the inner wall 'an annular groove into which its intake port opens and with which the intake openings of a sleeve piston are adapted to register. V

19. In an internal combustion engine, the combinationof a cylinder having intake and exhaust ports in its wall; opposed pistons in the. cylinder of which one is asleeve piston having intake and 1 exhaust ports adapted to register with the correspending cylinder ports, the intake ports insaid sleeve piston being nearer the open end. or, the

sleeve and cleared by the other piston when both 7 air admission ports so arranged that said heads are in heat-exchange relation with the admitted air.

v22. In an internal combustion engine, the combination oftwo rows of cylinders arranged in a V, each cylinder being open at both ends and having intake and exhaust ports near its inner and outer end,- respectively; opposed pistons in each cylinder, one being a sleeve piston having intake and exhaust ports adapted to register with the corresponding cylinder ports; a first chamber.

surrounding theintake ports ofall cylinders:

and a second chamber to the interior of, which I portions of all cylindersincluding theirvouter v ends are" exposed, said second chamber having air pistons are substantially in their innermost posi tion; and means tor lubricating the sliding surfaces of both pistons, said cylinder having a plu-' admission ports so" arranged that said exposed cylinder portions are in heat-exchange relation with theadmitted air.

JOHN J. McceRTHY. 

